On the information content of time- and angle-resolved photoelectron spectroscopy

A theory of time-resolved photoelectron spectroscopy from coherent rotational wavepackets is developed within a density matrix framework, expressing the signal as a partial wave series of rotational operators that tie the underlying electronic and rotational dynamics. The theory is applied to suggest and explore two potential applications of time- and angle-resolved photoelectron signals. First, we consider the possibility of extracting the bound-free electronic dipole matrix elements that underlie the ionization process from experimental data. Next, we investigate the extent to which photoelectron images could serve to map the time-evolving rotational probability distribution, thus providing insights into rotational coherences.